Adipose thermogenesis is repressed in obesity, reducing the homeostatic capacity to compensate for chronic overnutrition. Inflammation inhibits adipose thermogenesis, but little is known about how this occurs. Here we show that the innate immune transcription factor IRF3 is a strong repressor of thermogenic gene expression and oxygen consumption in adipocytes. IRF3 achieves this by driving expression of the ubiquitin-like modifier ISG15, which becomes covalently attached to glycolytic enzymes, thus reducing their function and decreasing lactate production. Lactate repletion is able to restore thermogenic gene expression, even when the IRF3-ISG15 axis is activated. Mice lacking ISG15 phenocopy mice lacking IRF3 in adipocytes, as both have elevated energy expenditure and are resistant to diet-induced obesity. These studies provide a deep mechanistic understanding of how the chronic inflammatory milieu of adipose tissue in obesity prevents thermogenic compensation for overnutrition.
Shuai Yan, Manju Kumari, Haopeng Xiao, Christopher Jacobs, Shihab Kochumon, Mark Jedrychowski, Edward Chouchani, Rasheed Ahmad, Evan D. Rosen
Multiple studies have shown loss of SARS-CoV-2 specific antibodies over time after infection, raising concern that humoral immunity against the virus is not durable. If immunity wanes quickly, millions of people may be at risk for reinfection after recovery from COVID-19. However, memory B cells (MBC) could provide durable humoral immunity even if serum neutralizing antibody titers decline. We performed multi-dimensional flow cytometric analysis of S protein receptor binding domain (S-RBD)-specific MBC in cohorts of ambulatory COVID-19 patients with mild disease (n = 7), and hospitalized patients with moderate to severe disease (n = 7), at a median of 54 (39-104) days after symptom onset. We detected S-RBD-specific class-switched MBC in 13 of 14 participants, failing only in the individual with lowest plasma levels of anti-S-RBD IgG and neutralizing antibodies. Resting MBC (rMBC) made up the largest proportion of S-RBD-specific MBC in both cohorts. FCRL5, a marker of functional memory on rMBC, was more dramatically upregulated on S-RBD-specific rMBC after mild infection than after severe infection. These data indicate that most SARS-CoV-2-infected individuals develop S-RBD-specific, class-switched rMBC that resemble germinal center-derived B cells induced by effective vaccination against other pathogens, providing evidence for durable B cell-mediated immunity against SARS-CoV-2 after mild or severe disease.
Clinton O. Ogega, Nicole E. Skinner, Paul W. Blair, Han-Sol Park, Kirsten Littlefield, Abhinaya Ganesan, Santosh Dhakal, Pranay Ladiwala, Annukka A.R. Antar, Stuart C. Ray, Michael J. Betenbaugh, Andrew Pekosz, Sabra L. Klein, Yukari C. Manabe, Andrea L. Cox, Justin R. Bailey
Background. Vaccines that block human-to-mosquito Plasmodium transmission are needed for malaria eradication and clinical trials have targeted zygote antigen Pfs25 for decades. We reported that a Pfs25 protein-protein conjugate vaccine formulated in alum adjuvant induced significant serum functional activity in both US and Malian adults. However, antibody titers declined rapidly, and transmission-reducing activity required four vaccine doses. Functional immunogenicity and durability must be improved before advancing TBV further in clinical development. We hypothesized that the pre-fertilization protein Pfs230 alone or in combination with Pfs25 would improve functional activity.Methods. Transmission-blocking vaccine candidates based on gamete antigen Pfs230 or Pfs25 were conjugated with Exoprotein A, formulated in Alhydrogel, and administered to mice, rhesus macaques, and humans. Antibody titers were measured by ELISA and transmission-reducing activity was assess by the Standard Membrane Feeding Assay. Results. Pfs25-EPA/Alhydrogel and Pfs230D1-EPA/Alhydrogel induced similar serum functional activity in mice, but Pfs230D1-EPA induced significantly greater activity in rhesus monkeys that was enhanced by complement. In U.S. adults, two vaccine doses induced complement-dependent activity in 4 of 5 Pfs230D1-EPA/Alhydrogel recipients but no significant activity in five Pfs25-EPA recipients, and combination with Pfs25-EPA did not increase activity over Pfs230D1-EPA alone.Conclusion. The complement-dependent functional immunogenicity of Pfs230D1-EPA represents a significant improvement over Pfs25-EPA in this comparative study. The rhesus model is more predictive of the functional human immune response to Pfs230D1 than is the mouse model. Trial Registration. ClinicalTrials.gov NCT02334462Funding. This work was supported by the Intramural Research Program of the National Institute of Allergy and Infectious Diseases, National Institutes of Health.
Sara A. Healy, Charles F. Anderson, Bruce J. Swihart, Agnes Mwakingwe-Omari, Erin E. Gabriel, Hope Decederfelt, Charlotte V. Hobbs, Kelly M. Rausch, Daming Zhu, Olga Muratova, Raul Herrera, Puthupparampil V. Scaria, Nicholas J. MacDonald, Lynn E. Lambert, Irfan Zaidi, Camila H. Coelho, Jonathan P. Renn, Yimin Wu, David L. Narum, Patrick E. Duffy
Background: Circulating SARS-CoV-2 RNA may represent a more reliable indicator of infection than nasal RNA, but RT-qPCR lacks diagnostic sensitivity for blood samples. Methods: A CRISPR-augmented RT-PCR assay that sensitively detects SARS-CoV-2 RNA was employed to analyze viral RNA kinetics in longitudinal plasma samples from nonhuman primates (NHP) after virus exposure; to evaluate the utility of blood SARS-CoV-2 RNA detection for COVID-19 diagnosis in adults cases confirmed by nasal/nasopharyngeal swab RT-PCR results; and to identify suspected COVID-19 cases in pediatric and at-risk adult populations with negative nasal swab RT-qPCR results. All blood samples were analyzed by RT-qPCR to allow direct comparisons. Results: CRISPR-augmented RT-PCR consistently detected SARS-CoV-2 RNA in the plasma of experimentally infected NHPs from 1 to 28 days post-infection, and these increases preceded and correlated with rectal swab viral RNA increases. In a patient cohort (n=159), this blood-based assay demonstrated 91.2% diagnostic sensitivity and 99.2% diagnostic specificity versus a comparator RT-qPCR nasal/nasopharyngeal test, while RT-qPCR exhibited 44.1% diagnostic sensitivity and 100% specificity for the same blood samples. This CRISPR-augmented RT-PCR assay also accurately identified COVID-19 patients with one or more negative nasal swab RT-qPCR result. Conclusion: Results of this study indicate that sensitive detection of SARS-CoV-2 RNA in blood by CRISPR-augmented RT-PCR permits accurate COVID-19 diagnosis, and can detect COVID-19 cases with transient or negative nasal swab RT-qPCR results, suggesting that this approach could improve COVID-19 diagnosis and the evaluation of SARS-CoV-2 infection clearance, and predict the severity of infection.
Zhen Huang, Bo Ning, He S. Yang, Brady M. Youngquist, Alex Niu, Christopher J. Lyon, Brandon J. Beddingfield, Alyssa C. Fears, Chandler H. Monk, Amelie E. Murrell, Samantha J. Bilton, Joshua P. Linhuber, Elizabeth B. Norton, Monika L. Dietrich, Jim K. Yee, Weihua Lai, John W. Scott, Xiao-Ming Yin, Jay Rappaport, James E. Robinson, Nakhle S. Saba, Chad J. Roy, Kevin J. Zwezdaryk, Zhen Zhao, Tony Y. Hu
Most clinically used anti-cancer monoclonal antibodies (mAbs) are of the IgG isotype, which can eliminate tumor cells through natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity and macrophage-mediated antibody-dependent phagocytosis. IgG, however, ineffectively recruits neutrophils as effector cells. IgA mAbs induce migration and activation of neutrophils through the IgA Fc receptor (FcαRI), but are unable to activate NK cells and have poorer half-life. Here, we combine the agonistic activity of IgG mAbs and FcαRI targeting in a therapeutic bispecific antibody format. The resulting TrisomAb molecules recruited NK cells, macrophages and neutrophils as effector cells for eradication of tumor cells in vitro and in vivo. Moreover, TrisomAb had long in vivo half-life and strongly decreased B16F10gp75 tumor outgrowth in mice. Importantly, neutrophils of colorectal cancer patients effectively eliminated tumor cells in the presence of anti-epidermal growth factor receptor (EGFR) TrisomAb, but were less efficient in mediating killing in the presence of IgG α-EGFR mAb (cetuximab). The clinical application of TrisomAb may provide high potential alternatives for cancer patients that do not benefit from current IgG mAb therapy.
Niels Heemskerk, Mandy Gruijs, A. Robin Temming, Marieke H. Heineke, Dennis Y. Gout, Tessa Hellingman, Cornelis W. Tuk, Paula J. Winter, Suzanne Lissenberg-Thunnissen, Arthur E.H. Bentlage, Marco De Donatis, Marijn Bögels, Thies Rösner, Thomas Valerius, Jantine E. Bakema, Gestur Vidarsson, Marjolein van Egmond
Neutrophils amplify inflammation in lupus through release of neutrophil extracellular traps (NETs). The endoplasmic reticulum stress sensor inositol-requiring enzyme 1 alpha (IRE1α) has been implicated as a perpetuator of inflammation in various chronic diseases; however, IRE1α has been little studied in relation to neutrophil function or lupus pathogenesis. Here, we found that neutrophils activated by lupus-derived immune complexes demonstrate markedly increased IRE1α ribonuclease activity. Importantly, heightened IRE1α activity was also detected in neutrophils isolated from lupus patients, where it correlated with global disease activity. Immune complex-stimulated neutrophils produced both mitochondrial reactive oxygen species (mitoROS) and the activated form of caspase-2 in IRE1α-dependent fashion, while inhibition of IRE1α mitigated immune complex-mediated NETosis (both in human neutrophils and in a mouse model of lupus). Administration of an IRE1α inhibitor to lupus-prone MRL/lpr mice over eight weeks reduced mitochondrial ROS levels in peripheral blood neutrophils, while also restraining plasma-cell expansion and autoantibody formation. In summary, these data are the first to identify a role for IRE1α in the hyperactivity of lupus neutrophils, with this pathway apparently upstream of mitochondrial dysfunction, mitochondrial ROS formation, and NETosis. Inhibition of the IRE1α pathway appears to be a novel strategy for neutralizing NETosis in lupus, and potentially other inflammatory conditions.
Gautam Sule, Basel H. Abuaita, Paul A. Steffes, Andrew T. Fernandes, Shanea K. Estes, Craig J. Dobry, Deepika Pandian, Johann E. Gudjonsson, J. Michelle Kahlenberg, Mary X. O'Riordan, Jason S. Knight
Ovarian cancer (OC) is the most deadly gynaecological malignancy with unmet clinical need for new therapeutic approaches. The relaxin peptide is a pleiotropic hormone with reproductive functions in the ovary. Relaxin induces aggressive cell growth in several types of cancer, but the role of relaxin in OC is poorly understood. Here, we demonstrate that relaxin and its associated G-protein coupled receptor RXFP1 form an autocrine signaling loop essential for OC in vivo tumorigenesis, cell proliferation and viability. We have found that relaxin signaling activates expression of pro-oncogenic pathways including RHO, MAPK, Wnt, and Notch. We find that relaxin is detectable in OC tumors, ascites and serum. Further, inflammatory cytokines IL-6 and TNF-α activate transcription of relaxin via recruitment of STAT3 and NFκB to the proximal promoter initiating an autocrine feedback loop that potentiates expression. Inhibition of RXFP1 or relaxin increases cisplatin sensitivity of OC cell lines and abrogates in vivo tumor formation. Finally, we demonstrate that a relaxin neutralizing antibody reduces OC cell viability and sensitizes cells to cisplatin. Collectively, targeting relaxin-RXFP1 signaling offers a potential new therapeutic strategy for OC.
Helen E. Burston, Oliver A. Kent, Laudine Communal, Molly L. Udaskin, Ren X. Sun, Kevin R. Brown, Euihye Jung, Kyle E. Francis, Jose La Rose, Joshua K. Lowitz, Ronny Drapkin, Anne-Marie Mes-Masson, Robert Rottapel
T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive hematologic malignancy with inferior outcome compared to B-cell ALL. Here, we showed that Runt-related transcription factor 2, RUNX2 was upregulated in high-risk T-ALL with KMT2A rearrangements (KMT2A-R) or an immature immunophenotype. In KMT2A-R cells, we identified RUNX2 as a direct target of the KMT2A chimeras, where it reciprocally bound the KMT2A promoter, establishing a regulatory feed-forward mechanism. Notably, RUNX2 was required for survival of immature and KMT2A-R T-ALL cells in vitro and in vivo. We reported direct transcriptional regulation of CXCR4 signaling by RUNX2, thereby promoting chemotaxis, adhesion and homing to medullary and extramedullary sites. RUNX2 enabled these energy-demanding processes by increasing metabolic activity in T-ALL cells through positive regulation of both glycolysis and oxidative phosphorylation. Concurrently, RUNX2 upregulation increased mitochondrial dynamics and biogenesis in T-ALL cells. Finally, as a proof of concept, we demonstrated that immature and KMT2A-R T-ALL cells were vulnerable to pharmacological targeting of the interaction between RUNX2 and its co-factor CBFβ. In conclusion, we showed that RUNX2 acts as a dependency factor in high-risk subtypes of human T-ALL through concomitant regulation of tumour metabolism and leukemic cell migration.
Filip Matthijssens, Nitesh D. Sharma, Monique Nysus, Christian K. Nickl, Huining Kang, Dominique R. Perez, Beatrice Lintermans, Wouter Van Loocke, Juliette Roels, Sofie Peirs, Lisa Demoen, Tim Pieters, Lindy Reunes, Tim Lammens, Barbara De Moerloose, Filip Van Nieuwerburgh, Dieter L. Deforce, Laurence C. Cheung, Rishi S. Kotecha, Martijn D. P. Risseeuw, Serge Van Calenbergh, Takeshi Takarada, Yukio Yoneda, Frederik W. van Delft, Richard B. Lock, Seth D. Merkley, Alexandre Chigaev, Larry A. Sklar, Charles G. Mullighan, Mignon L. Loh, Stuart S. Winter, Stephen P. Hunger, Steven Goossens, Eliseo F. Castillo, Wojciech Ornatowski, Pieter Van Vlierberghe, Ksenia Matlawska-Wasowska
Dystonia is a debilitating hyperkinetic movement disorder, which can be transmitted as a monogenic trait. Here, we describe homozygous frameshift, nonsense and missense variants in TSPOAP1, encoding the active zone RIM-binding protein 1 (RIMBP1), as a novel genetic cause of autosomal recessive dystonia in seven subjects from three unrelated families. Subjects carrying loss-of-function variants presented with juvenile-onset progressive generalized dystonia, associated with intellectual disability and cerebellar atrophy. Conversely, subjects carrying a pathogenic missense variant (p.Gly1808Ser) presented with isolated adult-onset focal dystonia. In mice, complete loss of RIMBP1, known to reduce neurotransmission, led to motor abnormalities reminiscent of dystonia, decreased Purkinje cell dendritic arborization, and reduced numbers of cerebellar synapses. In vitro analysis of the p.Gly1808Ser variant showed larger spike-evoked calcium transients and enhanced neurotransmission, suggesting that RIMBP1-linked dystonia can be caused by either reduced or enhanced rates of spike-evoked release in relevant neural networks. Our findings establish a direct link between dysfunction of the presynaptic active zone and dystonia and highlight the critical role played by well-balanced neurotransmission in motor control and disease pathogenesis.
Niccolò E. Mencacci, Marisa M. Brockmann, Jinye Dai, Sander Pajusalu, Burcu Atasu, Joaquin Campos, Gabriela Pino, Paulina Gonzalez-Latapi, Christopher Patzke, Michael Schwake, Arianna Tucci, Alan Pittman, Javier Simon-Sanchez, Gemma L. Carvill, Bettina Balint, Sarah Wiethoff, Thomas T. Warner, Apostolos Papandreou, Audrey Ker Shin Soo, Reet Rein, Liis Kadastik-Eerme, Sanna Puusepp, Karit Reinson, Tiiu Tomberg, Hasmet Hanagasi, Thomas Gasser, Kailash P. Bhatia, Manju A. Kurian, Ebba Lohmann, Katrin Õunap, Christian Rosenmund, Thomas Südhof, Nicholas Wood, Dimitri Krainc, Claudio Acuna
BACKGROUND. Immunization with replication-competent recombinant vectors provides exposure to transgene-encoded antigens in the context of inflammation that may drive more potent and durable immunity compared to non-replicating vaccines. To understand the features of a replicating vaccine that drive such responses we tested a replication-competent adenovirus type 4 encoding influenza virus H5 hemagglutinin (Ad4-H5-Vtn) administered by an oral capsule or via a tonsillar swab or nasal spray. METHODS. Viral shedding from the nose, mouth, and rectum was measured by PCR and culture. H5-specific IgG and IgA antibodies were measured by bead array binding assays. Serum antibodies were measured by a pseudovirus entry inhibition assay (PVEI), microneutralization (MN), and hemagglutinin inhibition (HAI). RESULTS. Ad4-H5-Vtn DNA was shed from most upper respiratory tract (URT)-immunized volunteers for 2-4 weeks, but cultured from only 60% of participants with a median duration of one day. Ad4-H5-Vtn vaccination induced increases in H5-specific CD4+ and CD8+ T cells in the peripheral blood and IgG and IgA in nasal, cervical and rectal secretions. URT immunizations induced high levels of serum neutralizing antibodies (NAb) to H5 which remained stable at week 26. The duration of viral shedding correlated with the magnitude of the NAb response at week 26. Adverse events (AE) were mild, and peak NAb titer was associated with overall AE frequency or duration. Serum neutralizing antibody titers could be boosted to very high levels 2-5 years after Ad4-H5-Vtn vaccination with recombinant H5 or inactivated split H5N1 vaccine. CONCLUSION. Replicating Ad4 delivered to the URT causes prolonged exposure to antigen, drives durable systemic and mucosal immunity, and is a promising platform for the induction of immunity against viral surface glycoprotein targets. TRIAL REGISTRATION. ClinicalTrials.gov NCT01443936, NCT01806909. FUNDING. Intramural and Extramural Research Programs of the NIAID, NIH; and the Centers of Influenza Virus Research and SurveillanceFunding. Intramural and Extramural Research Programs of the NIAID, NIH; and the Centers of Influenza Virus Research and Surveillance.
Kenta Matsuda, Stephen A. Migueles, Jinghe Huang, Lyuba Bolkhovitinov, Sarah Stuccio, Trevor Griesman, Alyssa A. Pullano, Byong H. Kang, Elise Ishida, Matthew Zimmerman, Neena Kashyap, Kelly M. Martins, Daniel Stadlbauer, Jessica Pederson, Andy Patamawenu, Nathaniel E. Wright, Tulley Shofner, Sean Evans, C. Jason Liang, Julián Candia, Angelique Biancotto, Giovanna Fantoni, April Poole, Jonathan Smith, Jeff Alexander, Marc Gurwith, Florian Krammer, Mark Connors
Intratumor heterogeneity is an important mediator of poor outcomes in many cancers, including breast cancer. Genetic subclones frequently contribute to this heterogeneity, however their growth dynamics and interactions remain poorly understood. PIK3CA and HER2 alterations are known to co-exist in breast and other cancers. Herein, we present data that describe the ability of oncogenic PIK3CA mutant cells to induce the proliferation of quiescent HER2 mutant cells through a cell-contact mediated mechanism. Interestingly, the HER2 cells proliferated to become the major subclone over PIK3CA counterparts both in vitro and in vivo. Furthermore, this phenotype was observed in both hormone receptor positive and negative cell lines, and was dependent on the expression of fibronectin from mutant PIK3CA cells. Analysis of human tumors demonstrated similar HER2:PIK3CA clonal dynamics and fibronectin expression. Our study provides insights into non-random subclonal architecture of heterogenous tumors, which may aid understanding of tumor evolution and future strategies for personalized medicine.
Swathi Karthikeyan, Ian G. Waters, Lauren Dennison, David Chu, Joshua Donaldson, Dong Ho Shin, D. Marc Rosen, Paula I. Gonzalez-Ericsson, Violeta Sanchez, Melinda E. Sanders, Morgan V. Pantone, Riley E. Bergman, Brad A. Davidson, Sarah C. Reed, Daniel J. Zabransky, Karen Cravero, Kelly Kyker-Snowman, Berry Button, Hong Yuen Wong, Paula J. Hurley, Sarah Croessmann, Ben Park
T regulatory cells (Treg) restrain both the innate and adaptive immune systems to maintain homeostasis. Allergic airway inflammation, characterized by a type 2 (Th2) response that results from a breakdown of tolerance to innocuous environmental antigens, is negatively regulated by Treg. We previously reported that prostaglandin I2 (PGI2) promoted immune tolerance in models of allergic inflammation; however, the effect of PGI2 on Treg function was not investigated. Treg from mice deficient in the PGI2 receptor IP (IP KO) had impaired suppressive capabilities during allergic airway inflammatory responses compared to mice with PGI2 signaling was intact. IP KO Treg had significantly enhanced expression of immunoglobulin-like transcript 3 (ILT3) compared to wild-type Treg, which may contribute to the impairment of the IP KO Treg’s ability to suppress Th2 responses. Using fate-mapping mice, we reported that PGI2 signaling prevents Treg reprogramming toward a pathogenic phenotype. PGI2 analogs promoted the differentiation of naïve T cells to Treg in both mice and humans via repression of β-catenin signaling. Finally, a missense variant in IP in humans was strongly associated with chronic obstructive asthma. Together, these data support that PGI2 signaling licenses Treg suppressive function and that PGI2 is a therapeutic target to enhance Treg function.
Allison E. Norlander, Melissa H. Bloodworth, Shinji Toki, Jian Zhang, Weisong Zhou, Kelli L. Boyd, Vasiliy V. Polosukhin, Jacqueline-Yvonne Cephus, Zachary J. Ceneviva, Vivek D. Gandhi, Nowrin U. Chowdhury, Louis-Marie Charbonnier, Lisa M. Rogers, Janey Wang, David M. Aronoff, Lisa Bastarache, Dawn C. Newcomb, Talal A. Chatila, R. Stokes Peebles, Jr.
Tyro3, AXL, and MerTK (TAM) receptors are activated in macrophages in response to tissue injury and as such have been proposed as therapeutic targets to promote inflammation resolution during sterile wound healing, including myocardial infarction. While the role of MerTK in cardioprotection is well-characterized, the unique role of the other structurally similar TAMs, and particularly AXL, in clinically-relevant models of myocardial ischemia-reperfused infarction (IRI) is comparatively unknown. Utilizing complementary approaches, validated by flow cytometric analysis of human and murine macrophage subsets and conditional genetic loss and gain of function, we uncover a unique maladaptive role for myeloid AXL during IRI in the heart. Cross signaling between AXL and TLR4 in cardiac macrophages directed a switch to glycolytic metabolism and secretion of proinflammatory IL-1β, leading to increased intramyocardial inflammation, adverse ventricular remodeling, and impaired contractile function. AXL interestingly functioned independently of cardioprotective MerTK to reduce the efficacy of cardiac repair, but like MerTK, was proteolytically cleaved. Administration of a selective small molecule AXL inhibitor alone improved cardiac healing, which was further enhanced in combination with blockade of MerTK cleavage. These data support further exploration of macrophage TAM receptors as therapeutic targets for myocardial infarction.
Matthew DeBerge, Kristofor Glinton, Manikandan Subramanian, Lisa D. Wilsbacher, Carla V. Rothlin, Ira Tabas, Edward B. Thorp
In inherited neurodevelopmental diseases, pathogenic processes unique to critical periods during early brain development may preclude effectiveness of gene modification therapies applied later in life. We explored this question in a mouse model of DYT1 dystonia, a neurodevelopmental disease caused by a loss-of-function mutation in the TOR1A gene encoding torsinA. To define the temporal requirements for torsinA in normal motor function and gene replacement therapy, we developed a mouse line enabling spatiotemporal control of the endogenous torsinA allele. Suppressing torsinA during embryogenesis caused dystonia-mimicking behavioral and neuropathological phenotypes. Suppressing torsinA during adulthood, however, elicited no discernible abnormalities, establishing an essential requirement for torsinA during a developmental critical period. The developing CNS exhibited a parallel “therapeutic critical period” for torsinA repletion. While restoring torsinA in juvenile DYT1 mice rescued motor phenotypes, there was no benefit from adult torsinA repletion. These data establish a unique requirement for torsinA in the developing nervous system and demonstrate that the critical period genetic insult provokes permanent pathophysiology mechanistically delinked from torsinA function. These findings imply that to be effective, torsinA-based therapeutic strategies must be employed early in the course of DYT1 dystonia.
Jay Li, Daniel S. Levin, Audrey J. Kim, Samuel S. Pappas, William T. Dauer
Omega-3 fatty acids from fish oil reduce triglyceride levels in mammals, yet the mechanisms underlying this effect have not been fully clarified despite the clinical use of omega-3 ethyl esters to treat severe hypertriglyceridemia and reduce cardiovascular disease risk in humans. Here we identified in bile a class of hypotriglyceridemic omega-3 fatty acid-derived N-acyl taurines (NATs) that, after dietary omega-3 fatty acid supplementation, increased to concentrations similar to those of steroidal bile acids. The biliary docosahexaenoic acid (DHA) containing NAT, C22:6 NAT, was increased in human and mouse plasma after dietary omega-3 fatty acid supplementation and potently inhibited intestinal triacylglycerol hydrolysis and lipid absorption. Supporting this observation, genetic elevation of endogenous NAT levels in mice impaired lipid absorption, while selective augmentation of C22:6 NAT levels protected against hypertriglyceridemia and fatty liver. When administered pharmacologically, C22:6 NAT accumulated in bile and reduced high fat diet-induced, but not sucrose-induced, hepatic lipid accumulation in mice, suggesting that C22:6 NAT was a negative feedback mediator that limited excess intestinal lipid absorption. Thus, biliary omega-3 NATs may contribute to the hypotriglyceridemic mechanism of action of fish oil and could influence the design of more potent omega-3 fatty acid-based therapeutics.
Trisha J. Grevengoed, Samuel A. J. Trammell, Jens S. Svenningsen, Mikhail Makarov, Thomas Svava Nielsen, Jens C. B. Jacobsen, Philip C. Calder, Marie E. Migaud, Benjamin Cravatt, Matthew P. Gillum
Multisystem inflammatory syndrome associated with the SARS-CoV-2 pandemic has recently been described in children (MIS-C), partially overlapping with Kawasaki disease (KD). We hypothesized that: 1) MIS-C and pre-pandemic KD cytokine profiles may be unique and justify the clinical differences observed; 2) SARS-CoV-2-specific immune complexes (IC) may explain the immunopathology of MIS-C. Seventy-four children were included: 14 MIS-C; 9 patients with positive SARS-CoV-2-PCR without MIS-C (COVID); 14 pre-pandemic KD and 37 healthy controls (HC). Thirty-four circulating cytokines were quantified in pre-treatment serum or plasma samples and the presence of circulating SARS-CoV-2 IC was evaluated in MIS-C patients. Compared to HC, MIS-C and KD groups showed most cytokines to be significantly elevated, with IFN-γ-induced response markers (including IFN-γ, IL-18, IP-10) and inflammatory monocytes activation markers (including MCP-1, IL-1α, IL-1RA) being the main triggers of inflammation. With linear discriminant analysis, MIS-C and KD profiles overlapped; however, a subgroup of MIS-C patients (MIS-Cplus) differentiated from the remaining MIS-C patients in IFN-γ, IL-18, GM-CSF, RANTES, IP-10, IL-1α and SDF-1 and incipient signs of macrophagic activation syndrome. Circulating SARS-CoV-2-IC were not detected in MIS-C patients. Our findings suggest a major role of IFN-γ in the pathogenesis of MIS-C, which may be relevant for therapeutic management.
Ana Esteve-Sole, Jordi Anton, Rosa Maria Pino-Ramírez, Judith Sanchez-Manubens, Victoria Fumadó, Clàudia Fortuny, María Rios-Barnes, Joan Sanchez-de-Toledo, Mónica Girona-Alarcón, Juan M. Mosquera, Silvia Ricart, Cristian Launes, Mariona Fernández de Sevilla, Cristina Jou, Carmen Muñoz-Almagro, Eva González-Roca, Andrea Vergara, Jorge Carrillo, Manel Juan, Daniel Cuadras, Antoni Noguera-Julian, Iolanda Jordan, Laia Alsina
Familial exudative vitreoretinopathy (FEVR) is a severe retinal vascular disease that causes blindness. FEVR has been linked to mutations in several genes associated with inactivation of the Norrin/β-catenin signaling pathway, but these account for only approximately 50% of cases. We report that mutations in CTNNA1 (α-catenin) cause FEVR by overactivating the β-catenin pathway and disrupting cell adherens junctions. Three heterozygous mutations in CTNNA1 (p.F72S, p.R376Cfs*27 and p.P893L) were identified by exome-sequencing. We further demon-strated that FEVR-associated mutations led to overactivation of Norrin/β-catenin signaling due to impaired protein interactions within the cadherin/catenin complex. The clinical features of FEVR were reproduced in mice lacking Ctnna1 in vascular endothelial cells (ECs) or with overactivat-ed β-catenin signaling by an EC-specific gain-of-function allele of Ctnnb1. In isolated mouse lung endothelial cells, both CTNNA1-P893L and F72S mutants failed to rescue either the dis-rupted F-ACTIN arrangement or VE-Cadherin and CTNNB1 distribution. Moreover, we discov-ered that compound heterozygous Ctnna1 F72S and a deletion allele could cause similar pheno-type. Furthermore, a LRP5 mutation, which activates Norrin/β-catenin signaling, was identified in a FEVR family and the corresponding knock-in mice exhibited partial FEVR-like phenotype. Our study demonstrates that precise regulation of β-catenin activation is critical for retinal vascu-lar development and provides new insights into the pathogenesis of FEVR.
Xianjun Zhu, Mu Yang, Peiquan Zhao, Shujin Li, Lin Zhang, Lulin Huang, Yi Huang, Ping Fei, Yeming Yang, Shanshan Zhang, Huijuan Xu, Ye Yuan, Xiang Zhang, Xiong Zhu, Shi Ma, Fang Hao, Periasamy Sundaresan, Weiquan Zhu, Zhenglin Yang
Hirschsprung disease (HSCR) is the most frequent developmental anomaly of the enteric nervous system with an incidence of 1/5000 live births. Chronic intestinal pseudo-obstruction (CIPO) is less frequent and classified as neurogenic or myogenic. Isolated HSCR has an oligogenic inheritance with RET as the major disease-causing gene, while CIPO is genetically heterogeneous, caused by mutations in smooth muscle-specific genes. Here, we describe a series of patients with developmental disorders including gastrointestinal dysmotility, and investigate the underlying molecular bases. Trio-exome sequencing led to the identification of biallelic variants in ERBB3 and ERBB2 in eight individuals variably associating HSCR, CIPO, peripheral neuropathy and arthrogryposis. Thorough gut histology revealed aganglionosis, hypoganglionosis and intestinal smooth muscle abnormalities. The cell-type-specific ErbB3 and ErbB2 function was further analysed in mouse single-cell RNA sequencing data and in a conditional ErbB3-deficient mouse model, revealing a primary role for ERBB3 in enteric progenitors. The consequences of the identified variants were evaluated using RT-qPCR on patient-derived fibroblasts or immunoblot assays on Neuro-2a cells overexpressing either wild-type or mutant proteins, revealing either decreased expression or altered phosphorylation of the mutant receptors. Our results demonstrate that dysregulation of ERBB3 or ERBB2 leads to a broad spectrum of developmental anomalies including intestinal dysmotility.
Thuy-Linh Le, Louise Galmiche, Jonathan Levy, Pim Suwannarat, Debby M.E.I. Hellebrekers, Khomgrit Morarach, Franck Boismoreau, Tom E.J. Theunissen, Mathilde Lefebvre, Anna Pelet, Jelena Martinovic, Antoinette Gelot, Fabien Guimiot, Amanda Calleroz, Cyril Gitiaux, Marie Hully, Olivier Goulet, Christophe Chardot, Severine Drunat, Yline Capri, Christine Bole-Feysot, Patrick Nitschke, Sandra Whalen, Linda Mouthon, Holly E. Babcock, Robert Hofstra, Irenaeus F.M. de Coo, Anne-Claude Tabet, Thierry J. Molina, Boris Keren, Alice S. Brooks, Hubert J.M. Smeets, Ulrika Marklund, Christopher T. Gordon, Stanislas Lyonnet, Jeanne Amiel, Nadège Bondurand
Women with pulmonary arterial hypertension (PAH) exhibit better right ventricular (RV) function and survival than men; however, the underlying mechanisms are unknown. We hypothesized that 17β-estradiol (E2), through estrogen receptor α (ERα), attenuates PAH-induced RV failure (RVF) by up-regulating the pro-contractile and pro-survival peptide apelin via a bone morphogenetic protein receptor 2 (BMPR2)-dependent mechanism. We report that ERα and apelin levels are decreased in RV homogenates from patients with RVF and from rats with maladaptive (but not adaptive) RV remodeling. RV cardiomyocyte apelin abundance increased in vivo or in vitro after treatment with E2 or ERα agonist. Studies employing ERα or ERβ null mice, ERα mutant rats or siRNA demonstrated that ERα is necessary for E2 to upregulate RV apelin. E2 and ERα increased BMPR2 in PH-RVs and in isolated RV cardiomyocytes, associated with ERα binding to the Bmpr2 promoter. BMPR2 is required for E2-mediated increases in apelin abundance, and both BMPR2 and apelin are necessary for E2 to enhance pro-survival signaling. E2 or ERα agonist rescued monocrotaline-PH and restored RV apelin and BMPR2 expression. We identified a novel cardioprotective E2-ERα-BMPR2-apelin axis in the RV. Harnessing this axis may lead to novel, RV-targeted therapies for PAH patients of either sex.
Andrea L. Frump, Marjorie E. Albrecht, Bakhtiyor Yakubov, Sandra Breuils Bonnet, Valerie Nadeau, Eve Tremblay, Francois Potus, Junichi Omura, Todd Cook, Amanda Fisher, Brooke E. Rodriguez, R. Dale Brown, Kurt R. Stenmark, C. Dustin Rubinstein, Kathy Krentz, Diana M. Tabima, Rongbo Li, Xin Sun, Naomi C. Chesler, Steeve Provencher, Sebastien Bonnet, Tim Lahm
The effect of SARS-CoV-2 infection on the pathophysiology of the placenta and its impact on pregnancy outcome has not yet been fully elucidated. Here, we present a comprehensive clinical, morphological, and molecular analysis of placental tissues from pregnant women with and without SARS-CoV-2 infection. SARS-CoV-2 could be detected in half of placental tissues from SARS-CoV-2-positive women. The presence of the virus was not associated with any distinctive pathological, maternal or neonatal outcome features. SARS-CoV-2 tissue load was low in all but one patient which exhibited severe placental damage leading to neonatal neurological manifestations. The placental transcriptional response induced by high viral load of SARS-CoV-2 showed an immunopathology phenotype similar to autopsy lung tissues from patients with severe COVID-19. This finding contrasted with the lack of inflammatory response in placental tissues from SARS-CoV-2-positive women with low viral tissue load and from SARS-CoV-2-negative women. Importantly, no evidence of vertical transmission of SARS-CoV-2 was found in any newborns, suggesting that the placenta may be an effective maternal-neonatal barrier against the virus even in the presence of severe infection. Our observations suggest that severe placental damage induced by the virus may be detrimental for the neonate independently of vertical transmission.
Fulvia Milena Cribiù, Roberta Erra, Lorenza Pugni, Carlota Rubio-Perez, Lidia Alonso, Sara Simonetti, Giorgio A. Croci, Garazi Serna, Andrea Ronchi, Carlo Pietrasanta, Giovanna Lunghi, Anna Maria Fagnani, Maria Piñana, Matthias S. Matter, Alexandar Tzankov, Luigi Terracciano, Andres Anton, Enrico Ferrazzi, Stefano Ferrero, Enrico Iurlaro, Joan Seoane, Paolo Nuciforo